<?php  if ( ! defined('BASE_PATH')) exit('No direct script access allowed');
/////////////////////////////////////////////////////////////////////////////
//
// SuperPHP - 快速的中文PHP框架
//
// @package		SuperPHP
// @author		hmw@superphp.org
// @copyright	Copyright (c) 2010, SuperPHP.ORG
// @license		http://www.superphp.org/user_guide/license.html
// @link		http://www.superphp.org
// @since		Version 1.0
//
// 许可协议请查看 http://www.SuperPHP.org/
//
/////////////////////////////////////////////////////////////////////////////

// ------------------------------------------------------------------------

/**
 * MySQL Utility Class
 *
 * @category	Database
 * @author		hmw@superphp.org
 * @link		http://www.superphp.org
 */
class Super_Db_mysql_utility extends Super_Db_Utility {

	/**
	 * List databases
	 *
	 * @access	private
	 * @return	bool
	 */
    private function _list_databases() {
        return "SHOW DATABASES";
    }

	// --------------------------------------------------------------------

	/**
	 * Optimize table query
	 *
	 * Generates a platform-specific query so that a table can be optimized
	 *
	 * @access	private
	 * @param	string	the table name
	 * @return	object
	 */
	private function _optimize_table($table){
		return "OPTIMIZE TABLE ".$this->db->_escape_identifiers($table);
	}

	// --------------------------------------------------------------------

	/**
	 * Repair table query
	 *
	 * Generates a platform-specific query so that a table can be repaired
	 *
	 * @access	private
	 * @param	string	the table name
	 * @return	object
	 */
    private function _repair_table($table) {
        return "REPAIR TABLE ".$this->db->_escape_identifiers($table);
    }

	// --------------------------------------------------------------------
	/**
	 * MySQL Export
	 *
	 * @access	private
	 * @param	array	Preferences
	 * @return	mixed
	 */
    private function _backup($params = array()) {
        if (count($params) == 0) {
            return FALSE;
        }

        // Extract the prefs for simplicity
        extract($params);

        // Build the output
        $output = '';
        foreach ((array)$tables as $table) {
            // Is the table in the "ignore" list?
            if (in_array($table, (array)$ignore, TRUE)) {
                continue;
            }

            // Get the table schema
            $query = $this->db->query("SHOW CREATE TABLE `".$this->db->database.'`.'.$table);

            // No result means the table name was invalid
            if ($query === FALSE) {
                continue;
            }

            // Write out the table schema
            $output .= '#'.$newline.'# TABLE STRUCTURE FOR: '.$table.$newline.'#'.$newline.$newline;

            if ($add_drop == TRUE) {
                $output .= 'DROP TABLE IF EXISTS '.$table.';'.$newline.$newline;
            }

            $i = 0;
            $result = $query->result_array();
            foreach ($result[0] as $val) {
                if ($i++ % 2) {
                    $output .= $val.';'.$newline.$newline;
                }
            }

            // If inserts are not needed we're done...
            if ($add_insert == FALSE) {
                continue;
            }

            // Grab all the data from the current table
            $query = $this->db->query("SELECT * FROM $table");

            if ($query->num_rows() == 0) {
                continue;
            }

            // Fetch the field names and determine if the field is an
            // integer type.  We use this info to decide whether to
            // surround the data with quotes or not

            $i = 0;
            $field_str = '';
            $is_int = array();
            while ($field = mysql_fetch_field($query->result_id)) {
                // Most versions of MySQL store timestamp as a string
                $is_int[$i] = (in_array(
                        strtolower(mysql_field_type($query->result_id, $i)),
                        array('tinyint', 'smallint', 'mediumint', 'int', 'bigint'), //, 'timestamp'),
                        TRUE)
                        ) ? TRUE : FALSE;

                // Create a string of field names
                $field_str .= '`'.$field->name.'`, ';
                $i++;
            }

            // Trim off the end comma
            $field_str = preg_replace( "/, $/" , "" , $field_str);


            // Build the insert string
            foreach ($query->result_array() as $row) {
                $val_str = '';

                $i = 0;
                foreach ($row as $v) {
                    // Is the value NULL?
                    if ($v === NULL) {
                        $val_str .= 'NULL';
                    } else {
                        // Escape the data if it's not an integer
                        if ($is_int[$i] == FALSE) {
                            $val_str .= $this->db->escape($v);
                        } else {
                            $val_str .= $v;
                        }
                    }

                    // Append a comma
                    $val_str .= ', ';
                    $i++;
                }

                // Remove the comma at the end of the string
                $val_str = preg_replace( "/, $/" , "" , $val_str);

                // Build the INSERT string
                $output .= 'INSERT INTO '.$table.' ('.$field_str.') VALUES ('.$val_str.');'.$newline;
            }

            $output .= $newline.$newline;
        }

        return $output;
    }

	/**
	 *
	 * The functions below have been deprecated as of 1.6, and are only here for backwards
	 * compatibility.  They now reside in dbforge().  The use of dbutils for database manipulation
	 * is STRONGLY discouraged in favour if using dbforge.
	 *
	 */

	/**
	 * Create database
	 *
	 * @access	private
	 * @param	string	the database name
	 * @return	bool
	 */
    private function _create_database($name) {
        return "CREATE DATABASE ".$name;
    }

	// --------------------------------------------------------------------

	/**
	 * Drop database
	 *
	 * @access	private
	 * @param	string	the database name
	 * @return	bool
	 */
    private function _drop_database($name) {
        return "DROP DATABASE ".$name;
    }

}
